An example of such variable valve mechanisms is a variable valve mechanism group 90 of a conventional example developed by the applicant (Patent Document 1). This variable valve mechanism group 90 is shown in FIG. 9. The variable valve mechanism group 90 includes one variable valve mechanism 90B for each cylinder 6 of an internal combustion engine.
Each variable valve mechanism 90B includes an input member 92 and output members 93, and the input member 92 and the output members 93 are swingably arranged on the same axis. The output members 93 drive valves 7 when the input member 92 is driven by a cam.
Each variable valve mechanism 90B further includes a slider 94 that engages with the input member 92 and the output members 93. When the slider 94 is displaced relative to the input member 92 and the output members 93 in the axial direction p, q, the output members 93 turn relative to the input member 92 in the swing direction due to the engagement of the slider 94 with the input member 92 and the output members 93.
The variable valve mechanism group 90 further includes a displacement device 96. The displacement device 96 displaces the sliders 94 of the variable valve mechanisms 90B at a time in the axial direction p, q to cause the displacement of each slider 94 relative to the input member 92 and the output members 93 and the turning of the output members 93 relative to the input member 92. The lift of the valves 7 of each cylinder 6 is increased or reduced accordingly.